<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<button onclick="c()">点击</button>
		<div id="div"></div>
	</body>
	<script type="text/javascript">
		function c(){
			var v = a();
			if(v == 1){
				document.getElementById('div').innerHTML = v;
			}
		}
		function a(){
			function b(){
				return 1;
			}
			return b();
		}
	</script>
</html>
